I. Field of the Invention
This invention relates generally to a catheter device for draining the urinary bladder, and more particularly to a bladder drainage catheter having an improved retention device integrally formed thereon.
II. Discussion of the Prior Art
The most common bladder drainage catheter in current use is the so-called Foley catheter. It comprises an elongated, double-lumen catheter where one lumen is open at a distal end thereof, providing a urine flow path through that lumen when the distal end is inserted through the urethra of a patient and into his/her urinary bladder. The second lumen leads from the proximal end of the catheter to an inflation port passing through the wall of the catheter body near its distal end and which is subtended by an expandable retention device. By injecting saline or other suitable fluid through the second lumen, the retention device is inflated within the bladder to a size precluding passage back down through the urethra.
One problem that quite frequently arises with the use of Foley catheters is that patients who may be semi-conscious due to pain relieving drugs and who find the catheter irritating, may try to extract it without help and without first deflating the retention balloon. This can result in severe trauma to the urethral lining. Another deficiency of the Foley catheter is that, at times, the retention balloon is inflated before the balloon reaches the bladder. This can result in severe damage to the urethra. No such premature inflation of a balloon in a urethra is possible with the present invention in that the retention device does not utilize a balloon.
When the prior art Foley catheter is used in male patients and is left in place over prolonged time periods, there is no provision for collecting and draining excretions from the prostate gland. The catheter body blocks the secretions from the prostate gland and this can lead to prostatitis and feeling of irritation and pain by the patient. The lack of regular irrigation of the prostatic urethra may also lead to urethritis.
A need, therefore, exists for a urinary drain that is comfortable when installed and that is retained in place against nominal pulling forces tending to extract it, but which can be removed without undue trauma to the neck of the bladder and the urethral lining, and which does not involve an inflatable balloon.
Also, a bladder drainage catheter for use in male patients should make provision for collection and drainage of prostatic fluids.
To obviate the aforementioned drawbacks of the prior art bladder drainage catheter, I have developed a urinary drain apparatus that comprises as a first element thereof an elongated, flexible, tubular member having a proximal end, a distal end and a lumen extending therebetween. The tubular member has an outer diameter permitting passage through a patient""s urethra and is of a length such that placement of a distal end portion into the patient""s urinary bladder will leave a proximal end portion of the tubular member extending beyond the urethral meatus. The distal end portion of the tubular member is preformed so that when unconstrained it forms a bladder retention coil that extends laterally from a longitudinal axis of the tubular member. The distal end portion further includes one or more apertures extending from a periphery of the tubular body member to the lumen through which urine may flow. To assist in placement and subsequent removal of the urinary drain, there is provided a tubular stiffening device that is dimensioned to be insertable into the lumen of the tubular drain member and is of a length so that when fully inserted, the bladder retention coil proximate the distal end thereof is straightened, the tubular stiffening device has an open distal end and an internal lumen for permitting urine flow therethrough. During placement, a trickle of urine out from the proximal end of the stiffening member serves to provide an indication that the distal end portion of the tubular body member has been inserted into the patient""s urinary bladder. Subsequent removal of the tubular stiffening member from the lumen of the tubular drain member allows the distal end portion thereof to reform the bladder retention coil.
By proper attention to the durometer of the tubular body member proximate its distal end portion and the manner in which it may be heat treated to induce the memory property causing the curl to form, the amount of force needed to extract the drain once it has been installed can be tailored so that pulling forces of a nominal amount, such as may be caused by normal body movements, will not result in the catheter pulling out from the patient. However, where more than nominal force is applied at the proximal end of the drain body, the drain body can be extracted without any appreciable injury to the urinary tract even though the tubular stiffening member is not reinserted for the purpose of straightening the curl before removal.
Furthermore, in accordance with the present invention, drainage apertures are provided through the wall of the drain body in a zone designed to span the prostate gland of a male patient when the distal end portion is resident within the urinary bladder and in its curl configuration. Hence, any exudate from the prostate gland can pass through the drain.